Eitms purpose
Stellar HDF Member
Joined: Jul 2009
Posts: 2,010
Likes: 140
From: Albuquerque New Mexico
Per the Moco literature "for rider comfort" I've ridden in 117 deg with eitms disabled, motor won't melt. Have 107,000 trouble free miles on that same engine.
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
it is to cool the motor internals- when active ( motor idle, no throttle input, road speed under 3 mph, so typically at a stop), the rear cylinder instead of getting fuel and spark and creating heat, will just pump air through the cylinder- that air will carry away heat from the motor internals.
previous to EITMS cop bikes were using the parade fan, and many owners tried them as well-
what's better- blowing air over the fins to remove heat- or reducing the production of heat ( or maybe a little of both)
the first production motor ( I know of) to use this type of cooling strategy was the Cadillac Northstar. Caddy didn;t know how to explain this to the public, so in ads they just said that you could drive the car 50 miles with no coolant in it- yes, in that version the 8 cylinders alternated cooling air, so the car could be driven- not far, not fast, but driven.
Cadillac had experimented with cylinder de-activation in the early 80's ( the 8/6/4), by the late 80's and the Northstar, engineers realized that cylinder deactivation could also be used for cooling.
The prime use for this in cars is fuel economy.
car motors are primarily liquid cooled
eitms is a great advance and although not intended to cool the rider, less motor heat will mean less rider roasting
on my model you can disable the eitms by rolling the throttle forward and holding while at idle- the cruise control icon will turn red, do again and the icon will turn green: eitms on
living in Phoenix ( 108ş right now) I experience high temps on my bike- eitms will come on once in a while stopped in heavy traffic or what stopped at a long light when the bike has been ridden a while and it is hot.
I'm glad it's there.
On my evo I had a problem once at very high heat, I won;t ride the panhead in this.
Mike
previous to EITMS cop bikes were using the parade fan, and many owners tried them as well-
what's better- blowing air over the fins to remove heat- or reducing the production of heat ( or maybe a little of both)
the first production motor ( I know of) to use this type of cooling strategy was the Cadillac Northstar. Caddy didn;t know how to explain this to the public, so in ads they just said that you could drive the car 50 miles with no coolant in it- yes, in that version the 8 cylinders alternated cooling air, so the car could be driven- not far, not fast, but driven.
Cadillac had experimented with cylinder de-activation in the early 80's ( the 8/6/4), by the late 80's and the Northstar, engineers realized that cylinder deactivation could also be used for cooling.
The prime use for this in cars is fuel economy.
car motors are primarily liquid cooled
eitms is a great advance and although not intended to cool the rider, less motor heat will mean less rider roasting
on my model you can disable the eitms by rolling the throttle forward and holding while at idle- the cruise control icon will turn red, do again and the icon will turn green: eitms on
living in Phoenix ( 108ş right now) I experience high temps on my bike- eitms will come on once in a while stopped in heavy traffic or what stopped at a long light when the bike has been ridden a while and it is hot.
I'm glad it's there.
On my evo I had a problem once at very high heat, I won;t ride the panhead in this.
Mike
Last edited by mkguitar; Aug 27, 2015 at 03:33 PM.
Grand HDF Member
Joined: Jun 2008
Posts: 4,012
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From: Central Fl
Outstanding HDF Member
Joined: Mar 2008
Posts: 2,306
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From: Everywhere
Eitms purpose
Originally Posted by mkguitar
it is to cool the motor ....
eitms is a great advance and although not intended to cool the rider
Mike
eitms is a great advance and although not intended to cool the rider
Mike
Road Warrior
Joined: Aug 2014
Posts: 1,937
Likes: 320
From: Vancouver, WA
I see your point but it's not meant to protect the motor. The engine can run very hot without damage. From the info I've gathered, it's more of a rider comfort thing and not engine protection but they both work hand in hand. I never have mine active. The newer touring bikes have the EITMS controlled by outside air temp (80 degrees or greater) as opposed to cyl head temp on the others.
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Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
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From: Phoenix '53, '88, '09 Big Twins
I think H-D may have re-phrased or dumbed- down the descriptions used in various publications from the moco.
from the 2014 Manual:
" The Engine Idle Temperature Management System (EITMS) can provide limited cooling of the rear cylinder for riders who frequently find themselves in prolonged idle conditions or traffic congestion "
Mike
from the 2014 Manual:
Mike
Last edited by mkguitar; Aug 27, 2015 at 02:49 PM.
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Club Member
Joined: Aug 2009
Posts: 203
Likes: 2
From: Boulder County, Colorado
On my '14 limited, I leave it enabled.
Even though the engine is designed to take the heat, why not enable it?
In addition to cooling the rear cylinder, it could keep the exhaust temp from rising while stopped and that is where you feel the heat. It might even save some fuel if you were in a lot of stop and go traffic.
Even though the engine is designed to take the heat, why not enable it?
In addition to cooling the rear cylinder, it could keep the exhaust temp from rising while stopped and that is where you feel the heat. It might even save some fuel if you were in a lot of stop and go traffic.
Road Warrior
Joined: Nov 2014
Posts: 1,962
Likes: 140
From: NY
I think H-D may have re-phrased or dumbed- down the descriptions used in various publications from the moco.
from the 2014 Manual:
" The Engine Idle Temperature Management System (EITMS) can provide limited cooling of the rear cylinder for riders who frequently find themselves in prolonged idle conditions or traffic congestion "
Mike
from the 2014 Manual:
Mike
Thats why its benefitial to go after the root cause which is excessive heat by installing Wards cooling fans (cools heads & upper cyls ) along with an ultracool oil cooler that has dual elec cooling fans that does a great job cooling the oil that collectively together reduced oil temp 50+ deg on my bike.
Benefits right off the bat when oil is running 50+ deg cooler in my bike's motor on a hot day are:
* MOTOR RETAINS MUCH BETTER / HIGHER OIL PRESSURE AT HOT IDLE & AT CRUISE TOO ALL TIMES.
* MOTOR DIDNT DETONATE ANYMORE ON HD'S REC 91 0CTANE FUEL.
* SAVED MONEY ON FUEL BECAUSE I DIDNT HAVE TO USE MORE EXPENSIVE 93 OCTANE FUEL ANYMORE . AND THE 93 FUEL ONLY REDUCED DETONATION BUT DIDNT FULLY STOP IT ON HOT DAYS UNDER LOAD BUT WITH THE OIL NOW RUNNING 50 DEG COOLER (HEADS & UPPER CYLS RUNNING COOLER TOO) THAT STOPPED THE DETONATION ALL TOGETHER EVEN WHEN RUNNING THE REC BY HD LOWER 91 OCTANE FUEL.
* VALVETRAIN REMAINS QUIET.
* LESS HEAT FROM MOTOR ONTO RIDER.
* MOTOR REMAINS MORE PWR/TRQ & CRISP THROTTLE RESPONSE EVEN ON ON HOTTER DAYS
SCOTT
